The search for two fishermen who have been missing since their trawler sank off the Cork coast nearly three weeks ago is to be gradually wound down.

The men's families have appealed again for volunteers to help with the search of Glandour Harbour, which entered its 20th day on Friday.

Skipper Michael Hayes, 52, and 24-year-old Egyptian crewman Saied Aly Eldin are still missing.

The land, sea and air search has been described as one of the most extensive ever undertaken in Ireland, but the Coast Guard is expected to wind down efforts early next week.

The Tit Bonhomme went down on January 15 close to Adam Island with six men on board, including the skipper, a 21-year-old Dublin man and four Egyptian men.

One of the Egyptian men survived and the bodies of the three others have since been recovered.

Coast Guard rescue boats, Navy divers and Garda helicopters have taken part in the 20-day search of the area.

A remotely-operated vehicle and camera was also deployed in the early days of the search to survey the sunken wreck and at one point, the search was expanded to cover an 18-mile radius of sea and coastline.

Dozens of local trawlers have also volunteered to take part in the search.